My Pokemon Died in the Mystery Dungeon

Yesterday, my chikorita died while battling in a dungeon. The difficulty level jumped up between scenarios from being super easy to really difficult, and it wasn't all that fun. I haven't turned my DS back on since then. It'll be a few days before I'm willing to go back and try again.

I think I'm missing something about battles or using my stuff. There's got to be a way to turn to face the thing I'm battling without taking a turn. And, I'm thinking I need to position myself better so that totodile can attack too.

In any case, the Mystery Dungeon is not as easy as I thought it was going to be. That, at once, makes me frustrated, and pleasantly surprised.